WCF对大量呼叫进行压力测试

Question

I'm currently developing a secure WCF service that will receive large numbers of calls, eg over 3000. My original approach has been to call the webservice methods using 'async' however rather quickly I realised that I needed to use the Task.WaitAll to ensure that all the calls were successfully made before the execution dropped out.

However, by utilising the WaitAll I'm now overloading the service with 70% of calls returning a combination of 'CommunicationException' and 'ServerTooBusyException' type messages. I have reviewed the WCF throttling options but still finding that these do not appear to have any direct effect, ie (Note: the webservice is being ran locally in this instance on Local IIS)

<serviceThrottling 
    maxConcurrentCalls="4096" 
    maxConcurrentSessions="65536" 
    maxConcurrentInstances="2147483647"/>

Running the webservice call sychronously works fine but runs too slow and I'm not terribly bothered about waiting for any callback from the webservice - I literally just need to 'fire and forget' these calls to the service.

Here's a rough example of what I'm doing on the client-side...

var numberOfIterations = 3000;
var allCalls = new List<Task>();

using (var service = new WebserviceServiceClient())
{
    for (var n = 0; n < numberOfIterations; n++)
    {
        var someObject = new SomeObject(DateTime.UtcNow);
        allCalls.Add(service.WebserviceMethodAsynch(SomeObject));
    }
}
Task.WaitAll(allCalls.ToArray());

Can anyone advise on an elegant approach to bombarding a WCF webservice from a client without an attritional amount of failed calls?

Note: one approach would be utilise queues (in this case Azure Queues), ironically the service being called is performing some minor preprocessing prior to adding the object onto a queue to be picked up by a separate, more intensive process.

Thanks in advance

Answer 1

Your client and your web service are not on the same machine, right? Anyway, I believe you'd better use a Load Test to achieve the results that you're looking for:

http://www.sandeepsnotes.com/2013/05/load-and-performance-testing-of-wcf.html